wheeler



N0. 6||,047. Patented Sept. 20, 1898. J. WHEELER.

METHOD OF AND APPARATUS FOR PRODUCING FILMS.

(Application filed June 16, 1897.) (No Model.) 3 Sheets-Sheet l.

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Patented Sept. 20, I898. J. WHEELER.

METHOD OF AND APPARATUS FDR PRODUCING FILMS.

(Application filed June 16, 1897.)

No Model.)

\D Uine gse mm. m. w Wm N0. 6H,U47. Patented Sept 20,1898.

J. WHEELER.

METHOD OF AND APPARATUS FOR PRODUCING FILMS.

(Application filed June 16, 1897.)

M MmleH a Sheets-Sheet s.

PATENT Fries.

JAMES \VHEELER, OF ILFRAOOMBE, ENGLAND.

METHOD OF AND APPARATUS FOR PRODUCING FILMS.

SPECIFICATION forming part of Letters Patent No. 611,047, datedseptember 20, 1898.

Application filed June 16, 1897. Serial No. 641,041. (No model.)Patented in Belgium October 21, 1897, No. 131,391, and in France January24, 1898,11'0. 274,328.

To all whom it may concern:

Be it known that I, J AMES WHEELER, a sub ject of the Queen of GreatBritain and Ireland, residing at Ilfracombe, in the county of Devon,England, have invented a Method of and Apparatus for Producing Films, ofwhich the following is a specification, and for which patents have beengrantedin France, No. 274,328, dated January'24, 1898, and in Belgium,No. 131,391, dated October 21, 1897.

This invention relates to the production of various articles of filmscontaining betulin or betulin anhydrid. According thereto the articleson which films are to be produced are exposed in a closed chamber tofumes produced by burning without flame a combustible materialcomprising or containing the epidermis or outer rind of birch bark to anamount bearing a suitable proportion to the area of the chamber.According to thereonditions under which the combustible material isburned there is'produced (a) an opaque film that is pervious tohydrofluoric acid, so that when produced on suitable glass and subjectedto the action of that acid it will enable the said acid to act upon theglass in such a manner as to impart to it a finelypitted translucentsurface, such as to render it highly suitable for use as focusing-glassor other purposes requiringa maximum amount of highly-diffused light,-or (b) a transparent film that ofiers great resistance to hydrofluoricacid and also to dampness and the attack of insects or fungoid growths.The opaque and pervious film I consider to 0on sist Wholly or chiefly ofpyrobetulin and the transparent of pyrobetulin anhydridthat is to say,respectively of betulin and betulin anhydrid produced by burning andconsequent dry distillation instead of by the action of a solvent, suchas boiling alcohol, Which has hitherto been the means employed forobtaining betulin.

In carrying my invention into practical effect I may employthecombustible material in the form of small blocks or tablets made bycompressing together a mixture comprising finely-ground epidermis ofbirch bark, preferably that of White birch or Bctula (dim, and anoxygen-carrier, such as nitrate of potassium. The percentage of nitrateof potassium in the material may vary. For the production of opaque ortransparent films for etching purposes there may be, for example, abouteight per cent. of nitrate of potassium, and when intended for producingtransparent films for protecting articles from damp, insect attack, dze,the percentage of nitrate of potassium may be from one to four. \Vhenless than two per cent. of nitrate of potassium is used, the mixtureshould be dried for a considerable time both before and aftercompression. In order to produce an opaque film, the tablets arearranged so as to give an air-space around each, whereas to produce atransparent film the tablets are placed close together, whereby a slowercombustion will be attained than with the former arrangement. The resultof the respective arrange- "ments is that Whereas in the one casepyrobetulin is obtained by the burning away of the cortical investmentof the betulin of the bark, in theother case this pyr'obetulin isconverted into its anhydrid by the more prolonged heating and slowerevolution of the fumes. The fumes are preferably filtered before beingdeposited, and in producing opaque films it is desirable to agitate thefumes given off in such a manner as to insure uniform deposition.

Figures 1 and 2 of the accompanying drawings are sectional views, takenat right angles to each other, of an apparatus suitable for filmingvarious articles according to this invention. Fig. 3 is a partial planrepresenting a support for a lamp. Fig. 4 is a detail View showing inelevation a portion of a support for the agitating apparatus. Fig.5shows the lamp half in vertical section and half in elevation. Figs. 6,7, and 8 are respectively a plan of a charge-plate, an elevation of anannular distance-piece, and a plan of a floorplate used in producingopaque films; and Figs. 9 and 10 are respectively plans of acharge-plate and a floor-plate used in producing transparent films.Figs. 5 to10, inclusive, are drawn to a larger scale than the otherfigures.

The apparatus shown comprises a filming chamber 1 of sheet-zinc, inwhich the articles to be filmed are placed and which has in its top anopening 2, preferably of circular shape,

through which it communicates with an upper compartment 3, formed by aconical cover 4, that fits upon the top of the chamber 1, formingtherewith around the opening 2 an air-tight joint by means of anindia-rubber ring 5 and a flange G or other suitable means.

The bottom of the chamber 1 may be closed in a snfficiently air-tightmanner by placing it upon a thick cloth or a pile of compressible paper.At the center of the opening 2 there is supported from the top of thechamber 1,

by means of bars 7, (see Fig. 3,) soldered or otherwise secured thereto,a suitable stand 8 for a lamp in which to burn the tablets. This lampmay, as shown, comprise a cylindrical cup 9, (see Fig. 5,) perforated,as shown, at its lower part to admit air and adapted in its up I perpart to support by means of brackets 10 a floor-plate 11, on which isplaced a ring or distance-piece 12, (see also Fig. 7,) which supports acharge-plate 13, in which the tablets are arranged with their loweredgesresting more or less on the floor-plate 11. To produce opaquefilms, the floor-plate may advantageonsly consist, as shown in Fig. 8,of two concentric rings 1% and 15 of metal, connected by radial pieces16 of metal, and the chargeplate 13 may, as shown in Fig. 6, be a plateof metal having a number of radial openings 17 made through it for thedue retention within them of the tablets with an air-space around each.(17 are air-holes.) The edges of the tablets will then rest more or lesson the ring 14:. For producing transparent films the floor-plate mayadvantageously consist,

as shown in Fig. 10, of a metal ring 18, having opposite sides connectedtogether by a number of parallel bars 19, and the chargeplate mayconsist, as shown in Fig. 9, of a similar ring 20, having twointersecting sets of bars 21 and 22, respectively, that connect oppositesides, but are placed at a comparatively great distance apart, andbetween which the tablets are arranged in close contact transversely tothe bars 19 of the floor-plate. The lamp is provided with a chimney 23of wiregauze, which is adapted to be supported, by means of pins 24, onthe upper end of the cup 9 and to project upward therefrom, and which issurrounded by and covered with filtering material 25, such as muslin.Instead of be ing supported by pins 24, resting on the upper end of thecup 9, the chimney 23 may rest upon and within an upwardlyoutwardlyextending flange secured to and a little below the upper edgeof the cup 9. Besides acting as a support to the chimney this collarwill serve to prevent air from entering the chimney between its wall andthe cup 9 to an injurious degree.

YVithin the conical cover 4:, which has a domed top 26, there isarranged a metal cylinder 27, supported by a cross-bar 28, which engagesin slots 29 in the cylinder 27 and is the cover 4,311.16. slots 32 (seeFi 4) in the ring 30. Vithin the cylinder 27 there is mounted a suitableapparatussuch, for example, as a vertical egg-whisk 33 for agitating theinternal atmospherethis apparatus having a crank-handle 34: or othersuitable operating means outside the cover 4 and the metal cylinder 27being provided below the agitating apparatus with a conical guide ordeflector 35.

In using apparatus constructed as described, the articles to be filmedhaving been placed in the filming-chamber 1 (care being taken that thearticles do not overlap one another or have nothing above them in thechamher, for the fumes descend after the manner of dew) and the tabletshaving been suitably arranged in the lamp, the latter are ignitedsimultaneously by means of a jet of gas caused to play upon their uppersurfaces, and any flame produced having been immediately extinguishedthe chimney 23 is placed upon the cup 9 and the lamp put upon its stand8. The conical cover 4- is then placed in position and the agitatingapparatus put into motion. The fumes on being formed rise upward throughthe cylinder 27 and are deflected by the guide 35 toward the center ofthe agitating apparatus 33, through which they pass to the top 26 of thecover 4-, which deflects them downward and causes them to descendbetween the cover 4: and the metal cylinder- 27 into the filmingchamber1 with the result that having been thus intimately mixed together andwith the air within the cover 4- they form uniform films upon thearticles in the filming-elntmber.

The an n ular recess formed by and between the cylinder 27 and theexternal surface of the deflector 35 serves to catch carbonaceous matterwhich collects upon the agitating apparatus and, especially if thelatter is not occasionally cleaned, is thrown from it to the sides ofthe cylinder in very thin flakes, which if allowed to fall upon the filmleave correspending marks upon it when finished.

The lamp and its charge when arranged for producing transparent filmsshould, especially in cold weather, be preparatorily heated as much asis consistent with its proper handling in order more completely toprevent at the outset the evolution of low-temperature fumes adapted toproduce opaque films. In the case of a filming-chamber of verylargc areait may be necessary to provide a fan which may be arranged to revolve ina circle slightly larger than the opening 2 and be slowly revolved by amotor, which would also work the agitating apparatus when producingopaque films; also, further, to facilitate the working a hook or ringmay be fitted at each corner and connected with a common rope or chainpassing over an overhead pulley for raising the chamber to allow of theremoval of the filmed material therefrom. Furthermore, the conical covermaybe made in two parts, forming an air-tight joint with each other bymeans of flanges, the lower part supporting the stand for the lamp andhaving one or more internal annular grooved depressions or channelsadapted to prevent condensed moisture from running down and falling uponthe films and the upper part carrying the agitating apparatus 33 and thecylinder 27.

For producing an opaque film on glass I have obtained satisfactoryresults with an apparatus, as above described, in which thefilming-chamber had a length of twenty-two inches, a breadth of sixteeninches, and a depth of eight inches, while the opening in its top wasnine inches in diameter, the height of the cover twelve inches, and thediameter of the cup of the lamp two and one-fourth inches, this beingadapted for circular tablets of about five-eighths of an inch indiameter. I have for this purpose and with this apparatus employedtablets weighing fifty grains-t'. e., in the ratio of twenty grains toeach superficial foot of the area of the filming-chamber. With thisapparatus I have found it suitable to operate the agitating apparatusfor fifteen minutes and then to allow a further fifteen minutes for thedue subsidence of the fumes. I have then removed the plates of glassfrom the chamber and exposed them in the open air, or preferably in adrying-chamber, to mature the films for not less than three days. Inproducing a transparent film on glass or metal and when filming othermaterial it is unnecessary to employ the agitating apparatus, which,together with the cylinder 27, is, before doing this, preferablyremoved.

For producing transparent films on glass or metal for etching purposes,suitable charges weigh from forty to sixty grains to the square foot ofthe area of the filmingohamber. For filming-chambers of larger area thanthat of which the dimensions have been given, while the proportions ofthe charges for transparent films should remain the same, that foropaque films should be reduced. Thus for a chamber of an area of ninesquare feeta suitable charge is one of two drams. Opaque films shouldnot be thicker than necessary, for the thicker they are of course thelonger must be the exposure to the action of the etching fluid, and evenwith the longer exposure the result is less satisfactory than with filmsof proper thickness. A safe rule to follow as regards glass (and as thesame thickness of film is correct for metals a trial slip of glass maybe filmed along with metal articles) is that on removing an opaque filmon glass from the filming-chamber immediately after the film has beendeposited a one-inch jet of gas should be seen clearly outlined throughthe filmed plate when the plate is held at a distance of three feet fromthe jet.

In filming a tube or like article it may advantageously be mounted on acore and rotated about a horizontal axis while the deposit is beingformed. Films may be produced on powders in this manner. If a powder belightly sifted over the floor of the filming-chamber and a film producedupon it, as hereinbefore described, an intimate mixture of the same(whether consisting of pyrobetulin or of pyrobetulin anhydrid) with thepowder can be easily effected immediately after the deposition of thefilm.

For reducing the epidermis of birch bark to a sufficiently fine powderto produce the combustible material or tablets I first pass it through adisintegrator until it is reduced to a finely-shredded condition. I thendry it by exposing it to the air freely and to a temperature of 120Fahrenheit during three days, and I then pass it repeatedly under heavystone-edge runners until sufficiently fine to pass through a sievehaving sixty holes to the linear inch.

Transparent films formed from a mixture containing about two per cent.of nitrate of potassium and produced in the manner described may beemployed for various purposes in addition to those hereinbefore referredto. For example, it has been found that lint having such a'filmdeposited upon it according to this invention acts very beneficially asa preventive to the formation of pus when applied to wounds. Plaster-s,bandages, paraffined paper, boric-acid powder, and wounddressingmaterials generally other than lint may of course be similarly treatedwith a like result. By so filming leather or fabrics,either simply oralternately with the application of oil or fatty matter, theappearance,durability, and resistance to damp or mildew are materiallyenhanced. Oorks likewise may advantageously be filmed to render themcapable of withstanding the action of acidulous or other corrodingsubstances. Again, two-percent. films produced according to thisinvention on paper impart to it a surface admirably adapted forreceiving impressions of engravings, &c., and in order to vary thenatural india-tint of the film when used for this purpose an addition offrom five to ten per cent. of asphaltum, dragons blood, or othersuitable sublimable material may be made in the composition of thetablets, the quantity of nitrate of potassium being proportionatelyincreased, if necessary, adequately to efiect their proper combustion.By filming (with two-per-cent. films) finished photographs having mat ordull surfaces or prints according to this invention fine effects ofsoftness and heightening of shadows can be produced. The tin amalgam orother silvering of mirrors, moreover, may have transparent films formedfrom a mixture containing eight per cent. of nitrate of potassium withthe addition of a suitable amount of a sublimable material adapted torender the films harder, such as ten per cent. of copal gum or kaurigum, and deposited upon the silvering in accordance with this inventionto protect it from cracking and becoming fogged by contact with a dampwall. The weight of charge for these various purposes is dependent uponthe degree of antiseptic protection or color required. Charges of fromten to sixty grains per square foot of the area of the filmingchambermay, however, sufficiently indicate the range. It is, moreover, obviousthat the translucent surface produced on glass or the mat or dullsurface produced on metal by means of an opaque film made according tothis invention may not only be plain, but may be of any desiredlettering or design, and this lettering or design may be either clear onan opaque or mat ground or opaque or mat on a clear ground. To obtain aclear lettering or design on an opaque or mat ground the lettering ordesign may be traced or worked direct upon the glass or metal afteropaque filming by using as a stop-out the anhydrid colored as describedin the next succeeding sentence, or in the case of glass by removingsuch parts of the film as are necessary to represent the lettering ordesign, in effecting which removal a certain portion of the film is leftbelow the removed parts, and the pressure employed by destroying itsporosity renders this portion capable of resisting the action of theacid for the requisite period of exposure, or the lettering or designmay be first drawn or stenciled on, transferred to, or photographicallydeposited upon the glass or metal in suitable resist (the best materialfor use with stencils or for transfers being betulin anhydrid producedin bulk in a manner similar to that hereinbefore described for two percent. transparent films and suitably colored by admixture withivory-black or Japan varnish ground up with linseed oil) and an opaquefilm be subsequently deposited, as hereinbefore described. After thisthe back of the plate is protected with Brunswick black or othersuitable resist and the plate is passed (care being taken to avoidcross-currents) evenly into the etching agent, which in the ease ofglass may be the ordinary fuming aqueous hydrofluoric acid of commerce,and from which, after the requisite number of seconds exposure,it istransferred to a bath adapted promptly to arrest the action of the acid.In the case of glass this bath may be a strong solution of commercialcarbonate of soda-z. 6., washing-sodaand in the case of metal it may bea whiting bath. The removal of the resist by suitable solvents and asubsequent scrubbing in soap and water with a stiff brush complete theprocess. To obtain an opaque or mat design or lettering on a clear orbright ground, one or more transparent films of the full capacity of thecharge-plate, according to the resisting power required, is or aredeposited on one surface of the glass or metal plate and the letteringor design traced or worked through the film or films, so as to exposecorresponding portions of the glass", (to facilitate the Working aslight opaque film may advantageously be deposited over the transparentfilm or films,) or an opaque film is first deposited upon the surface ofthe glass or metal and allowed to mature. Then a fern or other naturalobject or a stencil having the ground portion removed is placed evenlyupon the opaque film and a transparent film is produced over the whole,after which the fern or other objector stencil is removed. The processis completed in each case by etching to the required depth in the mannerabove described. By carrying the etching to a sufficient depth intoglass or metal a matrix may be formed for obtaining a gelatin or otherrelief from which a printing-surface may be made by any of the ordinarymethods, or a photographic negative suitable for the production of aprinting-surface may be obtained by photographing white etching producedby means of a transparent film upon ruby or orange flashed glass.

After a pattern has been produced 011 glass by etching, as justdescribed, suitable enamel colors may be worked into the design andfired.

To determine with accuracy the requisite number of seconds of exposureto the action of the etching-acid for an opaque film or of minutes for atransparent film on glass, a trial strip of the same glass and filmingis graduated and subjected to the acid for successively-increasedexposures corresponding to the graduations, and the results obtaineddetermine the proper exposures. The fitness of any given sample ofglass, more particularly for use with opaque films, is determined inlike manner. It is important to take care that the glass employed besuitablekinds yielding double fluorides are unsuitable-and the glassshould be so cleaned and polished that the breath will condense upon itin an even film, free from all irregular markings. It is also importantthat the opaque film should be properly matured, the measure of theopacity that it yields to the glass being proportional to its maturity,and that the action of the acid, which in this case must be stronge. 9.,the fuming aqueous hydrofluoric acid of commerce-upon the opaque film bepromptly arrested,after due exposure, by plunging the article into asolution of the carbonate of soda of commerce-i. 6., washing-soda.

It appears advisable for etching purposes to employ the transparent filmwithin a few hours after its formation, as within a day or two anopacity begins to appear. On the other hand, the longer the opaque filmis kept the better it becomes.

For etching metal articles after filming them according to thisinvention the etching fluid employed must of course be such as to form asoluble compound with the metal to be treated, and the liquid used toneutralize the etching agent must be alkaline or acid in accordancetherewith.

If for producing on a S111 ooth non-absorbent surface a transparent filmfor etching purposes instead of burning, as hereinbefore stated, amixture containing eight per cent. of nitrate of potassium there beburned a mixture containing a low proportion, such as one or two percent, of nitrate of potassium, there will be produced on such a surfacea film that presents an appearance of reticulation, and to an extentdependent upon this appearance is readily perviousto hydrofluoric acid,so that after maturing for two or three days in a dry atmosphere it willunder the action of a weak solution of that acid, such as the fu mingaqueous hydrofluoric acid of commerce mixed with not less than fifty percent. of Water, impart to the surface of ordinary glass, if it has beenproduced thereupon, a like appearance of reticulation, which whileoffering no increased resistance to the passage of light is yetsufficiently opaque for all purposes for which obscurity to vision aloneis required. Flashed glass treated in this way gives rise to brillianteffects of scintillation of light which render it well suited for use ascathedral glass. For producing reticulated films for etching purposes onglass or metal a suitable charge for the apparatus of which thedimensions are hereinbefore given weighs forty grains to the square footof the area of the filming-chamber. For chambers of larger area thecharge should be so regulated that after the contraction of the film,causing the appearance of reticulation, there would be no furtherdeposition. When a reticulated film has been properly deposited upon aplate of glass and matured, the glint of the glass is visible throughthe pervious portions of the film, whereas if there be furtherdeposition after contraction this will not be the case. The grain ofreticulated films produced in this way varies with the temperature ofthe air in the apparatus in which the filming is performed. Forinstance, the grain of afilm produced in an unwarmed chamber would befiner if formed in very cold weather than if formed in hot summerweather. The grain may also be made finer by reducing the charge belowthat of forty grains per square foot, hereinbefore mentioned. Toinsureuniformity in the size of the grain of a reticuluted film all that isnecessary is to equalize the temperature within the filming-chamber bysome suitable means. In the case of the apparatus of which thedimensions are hereinbefore given hot bricks placed in close contactwith the two ends of the chamber are adequate for the purpose. Chambersof larger area may each either be provided with a jacket, between whichand the chamber warmed air will be caused to pass, or have a lining ofasbestos to prevent radiation of heat.

Vhat I claim is- 1. Producing films containing pyrobetulin orpyrobetulin anhydrid on articles by compressing together into smallblocks or tablets a mixture comprising or containing finelygroundepidermis orouter rind of birch-bark and an oxygen-carrier such asnitrate of potassium, and exposing the said articles in a closed chamberto fumes produced by burning, without flame, a quantity of the saidblocks or tablets. bearing a suitable proportion to the area of the saidchamber, substantially as hereinbefore described.

2. Producing films containing pyrobetulin or pyrobetulin anhydrid onarticles by'compressing together into small blocks or tablets a mixturecomprising or containing finelyground epidermis or outer rind ofbirch-bark and an oxygen-carrier such as nitrate of potassium, exposingthe said articles in a closed chamber to fumes produced byburning,without flame, a quantity of the said blocksor tablets'bearing asuitable proportion to the area of the said chamber, and agitating thesaid fumes so as to mix them together. and with the air of the saidchamber, substantially as hereinbefore described.

3. Producing films containing pyrobetulin or pyrobetulin anhydrid onarticles by compressing together into small blocks or tablets a mixturecomprising or containing finely ground epidermis or outer rind ofbirch-bark and an oxygen-carrier such as nitrate of potassium, exposingthe said articles in a closed chamber to fumes produced by burning,without flame, a quantity of the said blocks or tablets bearing asuitable proportion to the area of the said chamber, and filtering thesaid fumes-before allowing them to form films on the articles treated,substantially as described.

4. Producing on articles films of pyrobetulin pervious to the action ofan etching agent so that articles so filmed will, under the action ofsuch an agent, be given a finelypitted surface, the said films beingproduced by compressing together a mixture comprising or containingfinely-groundepidermis or outer rind of birch-bark and an oxygen-carriersuch as nitrate of potassium, exposing the articles in a closed chamberto fumes produced by burning, without flame, a quantity of the saidcompressed mixture in the form of small blocks or tablets bearing asuitable proportion to the area of the said chamber and so arranged asto have an abundant supply of air, and agitating the said fumes so as tomix them together and with the air of the said chamber, substantially ashereinbefore described.

5. Apparatus for producing films on articles comprising a lowercompartment for containing the articles to be filmed, an uppercompartment communicating through an opening with the said lowercompartment, a lamp supported within the said upper c0m partment, and ahollow cylinder extending upward from the said lamp to Within a shortdistance from the top of said chamber, substantially as described andshown.

6. Apparatus for producing films on articles comprising a lowercompartment for 0011- taining the articles to be filmed, an uppercompartment communicating through an opening with the said lowercompartment, a lamp supported within the said upper compartment, ahollow cylinder extending up- IIO ward from the said lamp to within ashort distance from the top of the chamber, agitating apparatus arrangedwithin the said cyliuder, and means for operating the said agitatingapparatus from outside the said upper compartment, substantially asdescribed and shown.

7. Apparatus for producing films on articles comprising a closed chamberhaving a conical cover, a lamp situated centrally as regards the saidcover, and a hollow cylinder extending upward from the said lamp towithin a short distance from the said cover, substantially ashereinbefore described.

8. Apparatus for producing films on articles comprising a closed chamberhaving a conical cover, a lamp situated centrally as regards the saidcover, a hollow cylinder extending upward from the said lamp to within ashort distance from the top of the said cover,

an agitating apparatus above the said lamp,

means for operating the said agitating apparatus from outside the saidchamber, and a guide or deflector for directing into the said agitatingapparatus fumes rising up from the said lamp, substantially ashereinbefore described.

9. Apparatus for producing films on articles comprising a closedchamber, a lamp therein adapted to burn combustible material withoutl'lame, and means for filtering the fumes produced by the partialcombustion of the material as they are given oil, substantially ashereinbefore described.

10. Apparatus for producing films on articles comprising a closedchamber, a lamp adapted to burn combustible filming material withoutflame, means for filtering the fumes produced by the partial combustionof the said material as they are given off, and means for effecting theuniform deposition of a film upon the articles to be filmed,substantially as hereinbefore described.

11. Apparatus for producing films on articles comprising a closedchamber, a lamp adapted to burn combustible filming material withoutflame, means for filtering the fumes produced by the partial combustionof the said material they are given oil, means for agitating the fumesafter filtering, and means for eifecting the uniform distribution of afilm upon the articles to be filmed, substantially as hereinbcforedescribed.

12. For producing films on articles, a lamp comprising a receptacle toreceive combustible filming material and a chimne; having walls and acover of material adapted to filter fumes produced by the partialcombustion of the said filming material substantially as hereinbeforedescribed.

13. For producing films on articles, a lamp comprising a cup perforatedin its lower part and provided in its upper part with means forsupporting combustible filmin g material, and a chimney having walls anda cover of material adapted to filter fumes produced by the partialcombustion of the said filming material, substantially as hereinbeforedescribed.

lat. For producingfilms on articles, a lamp comprising a cup perforatedin its lower part and provided in its upper part with means forsupporting combustible filming material in such a manner as to allow itan abundant supply of air, and a chimney having walls and a cover ofmaterial adapted to filter fumes produced by the partial combustion ofthe said filming material, substantially as here inbefore described.

15. For producing films on articles, a lamp comprising a cup having itslower part perforated, means in the upper part of said cup adapted tosupport tablets of combustible filming material with an air-space aroundeach tablet, and a chimney having walls and a cover of material adaptedto filter fumes produced by the partial combustion of the said filmingmaterial, substantially as here inbefore described.

16. For producingfilms on articles, a lamp comprising a receptacle toreceive combustible filming material and comprising an openworkfloor-plate adapted to support the lower edges of the tablets, acharge'plate having radial openings each adapted to receive a tablet,and a distance-piece between the said floor-plate and the saidcharge-plate, and a chimney having walls and a cover of material adaptedto filter fumes produced by the partial combustion of the said filmingmaterial, substantially as hereinbefore described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

JAMES \VIIEELER.

\Vitnesses:

HERBERT KIDMAN, HAROLD DISMOND.

